This circuit is for a siren that can be used with any of the above alarms and also other types. The circuit is from a Radio Electronics magazine from May 1975.
An oscillator whose frequency can be adjusted between 500 Hz and 5 kHz with the use of a...
This circuit was found in Motorola documentation from 1969. The transistors are from that time. The...
This circuit brings together in a single set a preamplifier and an equalizer with several inputs. The...